A Multielectrode array for single-unit recording in the central nervous system has been under development at The University of Michigan. Preliminary results of the device indicate it could provide a remarkable advance for neurophysiological investigations in such areas as communicative processes and future applications in neural prostheses. Providing this device to neurophysiologists on a wide-spread basis would be necessary if the full potential of the device were to be realized. The array fabrication uses a novel combination of microelectronics and silicon micromachining utilizing a custom process. The Phase I objectives are to develop a process schedule compatible with industrial semiconductor process houses and identify the assembly procedures and device testing needed to produce a user-ready device. The ultimate goal is to make the multielectrode array commercially available after determining feasibility of cost-effective production. Additionally, the proposed research will contribute to other R&D efforts for a variety of biological sensors incorporating on-chip circuitry and sensing elements. Phase II objective are to implement fabrication and assembly schedules determined in the Phase I research and evaluate its yield, reliability, quality and economics.